Heater



Dec. 3l, 1940.

H. J. DE N. MOCOLLUM HEATER Filed July 31, 1939 www IIIIZWZ PatentedDec. v31 1940 UNITED STATES PATENT OFFICE HEATER Henryr J. De N.McCollum, Chicago, Ill. Application July 31, 1939, Serial No. 287,556

i` Claims.

l My invention relates generally to heaters of the internal combustiontype, and more particularly to improvements in such heaters whereby thesupply of the mixture of fuel and air to the comi bustion chamber isthermostatically controlled so as to make the mixture less rich when theheater has attained its normal operating temperature.

It is thus an object of my invention to provide an improved heaterhaving a thermostatically controlled means located within the body ofthe heater for admitting additional air to the cornbustion chamberthereof when the heater has attained normal operating temperature.

A further object is to provide an improved means for regulating the fuelmixture supplied to a heater of thel internal combustion type.

A further object is to provide an improved vthermostatically controlledmeans'for regulating the -fuel and air mixture supplied to an internalcom- :o bustion type heater, which is simple in construction,substantially noiseless in operation, which is durable, and which may beeconomically manufactured.

Other objects will appear from the following description, referencebeing had to the accompanying drawing, in which:

Figure l. is a fragmentary vertical sectional view-of a heater embodyingmy invention;

Figure 2 is an enlarged fragmentary sectional $0 view) of the combustionchamber and its fuel supply conduit;

Figure 3 is a transverse sectional View taken on the line 3723 of Figure2.

My invention is illustrated as being incorporated in a heaterparticularly designed for use yin heating the passenger compartment ofAan automobile, andis shown as attached to the dash or re wall III whichseparates the engine com-v partment from the passenger compartment .ofthe automobile. The heater comprises generally a casting I2 which has acombustion chamber I4 formed therein. Fuel is supplied to the combustionchamber from a suitable chamber I6 which may be the float bowl of theengine carburetor or any other suitable source of fuel, such as anauxiliary gasoline tank in which the gasoline is maintained at adefinite level. The gasoline isdrawn from the reservoir lithrough aconduit/I8 to a v carbureting device 20, where the fuel drawn throughthe conduit I8 is partially vaporized and mixed with an amount of air toform a rich mixture for starting purposes. The rich mixture is4 drawnthrough a tubular extension 22 forming `part of the casting I2, andthrough an insert tube 24 into the combustion chamber, the mixtureflowing -through apertures 26 formed around the periphery of a bailleplate 28.

The baille plate 28 has radially extending lugs 30 which snugly engagethe bore 32 formed in the casting I2, and are pressed against a shoulder34 5 formed at the 4end of the bore 32 by a sleeve or liner 36 which ispressed into the bore 32.

The liner 36 has a suitable aperture 38 formed therein to register witha correspondingly shaped opening formed in the side of the bore 32 toprol0 vide for ow of the fuel and air mixture into an igniter chamber 4Uwhich is provided with an igniter 42 which may be an electrically heatedcoil of Nichrome or similar resistance wire.

The left hand end of the combustion chamber l5` is partially closed byareigniter plug 44 which has a plurality of apertures 46 to permit flowof the products of combustion from the combustion chamber, and ispreferably made of a somewhat v porous ceramic material. The reigniterplug 44 20 is held in place by a split spring ring 48. I

The products from the `combustion chamber 4iiow through a circuitouspassageway formed in a radiator casting 5 0 and ilow from the latterthrough a vacuum compensating discharge nozzle 25 52 under the controlof a valve 54 which is manually operated by a control button 56.Operation .of the button 56 also controls the operation of electricalswitching mechanism 58 by which the I ow of energizing current to theigniter 42 and 3o the supply of current to an electric motor 60 arecontrolled.

The motor 60 drives a fan 62 which circulates air from the passengercompartment of the vehicle over heat radiator fins 64 which are in heat35 conducting relationship with the radiator 50. The products ofcombustion are withdrawn through a tubular extension 65 forming part ofthe casting I2 and through a conduit 68 connected thereto into theintake manifold I0 of the 40 automobile engine.

, The baiile plate 28 previously mentioned is made of thermostaticbimetal, and when coldhas its central portion pressed against andclosing the end of a tube 'I2 which is pressed into a com- 45 plementalbore 14 formed in the end of the tubular extension 22 ofthecasting I2.The outer end of the tube 12 is open to the atmosphere, but

its inner end, when the heater is at atmospheric temperature, is closedby the baille 28. Thus, 50 upon initiation of the operation of theheater by pulling outwardly onthe controlknob 56; a rich mixture isinitially supplied tothe combustion chamber by the carbureting device20. thus facilitating ignition of this mixture. 55

lil

However, after normal combustion within the combustion chamber ificommences, the heme plate 28 will become heated and due to its bimetalconstruction, gradually become deformed so as to move away from theinner end of the tube 12 t0- ward the shape in which the baiiie plate isshown in dotted lines in Fig. 2. Under these circumstances, atmosphericair will be admitted through the tube i2 and spread in a sheet-likeradiating stream over the surface of the bae 2d to be intimately mixedand aid in the further atomization of the gasoline in the mixture whichis projected against the baie plate 28 from the end of the tube 2d.

By virtue of this construction, there is a pi'onounced tendency for theincoming atmospheric air to break up any small globules of iuel whichhave not been completely atomized, and to secure a very intimate anduniform mixture.

It will be understood that after combustion has commenced, it is notnecessary to supply as rich a mixture'as is necessary for startingpurposes, and that combustion is more complete and there is less residuewhich may lbe deposited in the passageways of the radiator if themixture is made more lean after the heater has commenced normaloperation.

As the temperature of the combustion chamber casting and the temperatureoi' the heme plate 23 increases, the central portion of the baille platewill move slightly an increasing distance from the end of the air supplytube 12. The baille thus constitutes in eect a type of governor upon thecombustion which takes place in the combustion chamber i4, since as moreand more atmospheric air is drawn into the combustion chamber, this airitself will have a tendency to lower the temperature of the baiiie plate2B and cause it to 'flex in a. direction toward the end of tube 12. The

40 richness of the mixture is thus automatically regulated to maintaincombustion within'the chamber I4 under optimum conditions By.v selectionof a tube 12 having a bore of proper size, the regulation aiforded bythe bimetal baille plate 28 may readily be made to secure the optimummixture for combustion at the dif. ferent operating temperatures.

Since the central portion of the baille plate 28 moves away from the endof the tube 12 when 5 admi-.mm1 air is tov be admitted to the mixturesupplied tothe combustion chamber, there is no substantial tendency forthe baille 28 to ilutter or hunt. It thus forms, in effect, a dampedvalve -which is substantially noiseless. By virtue of the met that theheme :s 1s located within the heavy casting 22, and the only path forsound to travel from the baille to the atmosphere is through the longtube 12 such noise as may be occasioned by the striking of the bailleagainst the end of ,the tube- 12, due to variations in the intakemanifold vacuum, will not be transmitted in appreciable intensity to theatmosphere. I

While I have sh'own and described a particular fonn of my invention, itwill be apparent to those 05 skilled in the art that the underlyingprinciples asaaois closed by said battle plate, and a tube having oneend open to the atmosphere and its other end located adjacent saidbaille plate in position to be closed by the latter when at atmospherictemperature and to be uncovered in part when said baiie plate is heatedto a temperature approaching the normal operating temperature oi theheater, thereby to cause the mixture supplied to said combustion chamberto become less rich when said heater is in normal operation.

2.An automobile heater of the internal combustionvtype comprising acasting having a combustion chamber formed therein and having a tubularAextension communicating with said com` bustion chamber, a baille plateof thermostatic bimetal partially obstructing communication between saidtubular` extension and said combustion chamber, means for supplying afuel and air mixture to said tubular extension, and a conduit foradmitting atmospheric air for admixture with said fuel and air mixture,said conduit terminating closely adjacent said bafe so as to be closedthereby when said baille is at atmospheric temperature and to beuncoveredwhen said baille is heated to a predetermined temperature.

3. In an automobile heater having a. combustion chamber, a thermostaticbimetal valve partially closing one end of said combustion chamber, aconduit having one end open to the atmosphere and its other end locatedatUacent said valve in position to be closed by the latter when atatmospheric temperature and to be opened when said valve is heated to atemperature approaching the normal operating temperature of the heater,and means providing a passageway surrounding said conduit for supplyinga rich mixture of fuel and air to said combustion chamber.

4. In an automobile heater of the internal combustion type, thecombination of a part having a combustion chamber formed therein, meansforming a passageway for supplying a combustible mixture of fuel andair` to said chamber, a baille plate of thermostatic bimetal partiallyobstructing the end of said passageway, and a conduit for .supplyingatmospheric air for admixture to said combustible mixture, said conduitterminating adjacent said baille plate so as to be closed there by whenthe baille plate is at a relatively low temberature and to be openedwhen said baille plate is heated to a predetermined higher temperature.

HENRY J. DE N. MCCOLLUM.

